Is insulation worth it beyond the new construction standard?

We wanted to do a passive house and are now doing Kfw55. It's a good compromise, isn't it?

Let's continue with the windows. I assume regular windows have a value of 1.1 (triple glazing is probably standard nowadays?) and passive house windows 0.8. Heat loss is 86 kWh or 63 kWh per m2 per year. With 30 sqm of window area, this results in a difference of 690 kWh_thermal or 168 kWh_electric or 42.07 EUR per year. Calculated over 20 years, this amounts to 841.40 EUR, although I once read that insulating glass does not necessarily last 20 years.

841.40 EUR over 20 years - is there ever a reason to choose anything other than standard windows? Moreover - does something as delicate as argon-filled windows really last long?

By the way, my costs are calculated with a heat pump using household electricity (25 cents per kWh_electric) and without photovoltaic self-consumption, so more or less the worst case at the moment.

So an annual performance factor of 4.1 is rather hard to achieve even for the Geisha (although it is already a good one from the COP - 3.88 at A2/35). Please don't forget that you will need 2 of them if you want poor insulation... just as a side note. Whether it is worth it probably also depends on who you are building with and how. So our builder just builds the way he builds - that is always something like KFW55 or KFW70 (depending on the heating) - he just puts 16 cm of mineral wool on the wall. If you build with a big one whose strategy is to explore the maximum price point with tiered prices, it is usually less worthwhile.

Energy cost increases and resale value should perhaps be taken into consideration. imho the better standard should also be noticeable in a potential resale.

Insulation is actually relatively secondary when selling in 10-15 years. A house that is 15 years old today still has a reasonable value in terms of insulation. No one will care in 15 years whether it was built today with Kfw 70 or 55. In 15 years, the insulation will be technically outdated, the windows will have seen their best years, and the heating system might also need to be replaced soon. Depending on maintenance, the house will of course still make a very good impression.

I doubt that the insulation is really outdated, that the windows have seen better days, and above all, that the heating system needs to be replaced.

But I guess it’s due to the mindset of the disposable society...

Insulation outdated? The closer you get to the [Zero Energy House] today, the closer you are to the future standard. Energy-saving living probably won't go out of fashion...
My windows and the heating should also last until retirement, please.